Chemical hybridizing agents GSC and SX-1,were applied to study anthers breathing dehydrogenase activity,free proline content,protein content and protective enzyme activities of winter Brassica campestris ‘Longyou 6’ for two years.The results showed that:(1)SX-1 and GSC can induce male sterility on B.campestris plants,and sprayed of GSC using 0.6 mg/L or SX-1 using 9.0~10.0 mg/L had the best inducing effect.(2)The anther breathing dehydrogenase activity was significantly decreased after GSC and SX-1 treatment;Free proline content in leaves increased,while decreased in buds;Protein content of leaves had no significant change,but protein content of buds decreased;CAT and SOD activities of leaves increased,POD activity decreased,while CAT and SOD activity of the flower buds decreased,POD activity increased.Research showed that anthers breathing dehydrogenase activity,free proline content,protein content and protective enzyme activities of buds and leaves appeared exception after CHA treatment,and the anomaly became more significant with concentration increased,resulting in a lower metabolic rate of oxygen scavenging activity,the cell membrane lipid peroxidation enhanced and membrane structure destroyed,pollen development blocked,eventually causing male sterility.